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  • How to convert a power point pdf to a pdf that is easy to read on kindle?

    - by SpaceTrucker
    I have several power point presentations as pdfs. I would like to read them on the original kindle in landscape format. When I read the original on the kindle then a single slide won't fit on the kindles display. I thought the easiest way to convert the pdf was to repring it with a pdf printer. However I don't know the paper size to use. I already tried using Calibre as suggested by this question. However the output is not usable because of formatting issues. So what paper size should I use for the pdf printer to reprint them in landscape format or are there any other tools I could use for that task?

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  • How to convert OpenVZ OS templte to bootable to image file?

    - by Medi
    My question is how to convert a pre-created OpenVZ OS template which are in tar.gz format (such as these) to an image file in order to be able boot it with other virtualization solutions such as QEMU or VirtualBox. In order to achieve this, I made an empty image file, I partitioned it, and made two partition, a primary partition and a extended partition for swap. I made the first partition ext3 (0x83) and the other one swap (0x82). Then I made the first one bootable, and copied the content of tar.gz to the first partition. But when I try to boot, it hangs at the first stage of booting.

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  • How Do I Escape Apostrophes in Field Valued in SQL Server?

    - by Mikecancook
    I asked a question a couple days ago about creating INSERTs by running a SELECT to move data to another server. That worked great until I ran into a table that has full on HTML and apostrophes in it. What's the best way to deal with this? Lucking there aren't too many rows so it is feasible as a last resort to 'copy and paste'. But, eventually I will need to do this and the table by that time will probably be way too big to copy and paste these HTML fields. This is what I have now: select 'Insert into userwidget ([Type],[UserName],[Title],[Description],[Data],[HtmlOutput],[DisplayOrder],[RealTime],[SubDisplayOrder]) VALUES (' + ISNULL('N'''+Convert(varchar(8000),Type)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),Username)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),Title)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),Description)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),Data)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),HTMLOutput)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),DisplayOrder)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),RealTime)+'''','NULL') + ',' + ISNULL('N'''+Convert(varchar(8000),SubDisplayOrder)+'''','NULL') + ')' from userwidget Which is works fine except those pesky apostrophes in the HTMLOutput field. Can I escape them by having the query double up on the apostrophes or is there a way of encoding the field result so it won't matter?

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  • Stuck in a loop

    - by Luke
    while (true) { //read in the file StreamReader convert = new StreamReader("../../convert.txt"); //define variables string line = convert.ReadLine(); double conversion; int numberIn; double conversionFactor; //ask for the conversion information Console.WriteLine("Enter the conversion in the form (Amount, Convert from, Convert to)"); String inputMeasurement = Console.ReadLine(); string[] inputMeasurementArray = inputMeasurement.Split(','); //loop through the lines looking for a match while (line != null) { string[] fileMeasurementArray = line.Split(','); if (fileMeasurementArray[0] == inputMeasurementArray[1]) { if (fileMeasurementArray[1] == inputMeasurementArray[2]) { Console.WriteLine("The conversion factor for {0} to {1} is {2}", inputMeasurementArray[1], inputMeasurementArray[2], fileMeasurementArray[2]); //convert to int numberIn = Convert.ToInt32(inputMeasurementArray[0]); conversionFactor = Convert.ToDouble(fileMeasurementArray[2]); conversion = (numberIn * conversionFactor); Console.WriteLine("{0} {1} is {2} {3} \n", inputMeasurementArray[0], inputMeasurementArray[1], conversion, inputMeasurementArray[2]); break; } } else { Console.WriteLine("Please enter two valid conversion types \n"); break; } line = convert.ReadLine(); } } The file consists of the following: ounce,gram,28.0 pound,ounce,16.0 pound,kilogram,0.454 pint,litre,0.568 inch,centimetre,2.5 mile,inch,63360.0 The user will input something like 6,ounce,gram The idea is that it finds the correct line by checking if the first and second words in the file are the same as the second and third the user enters. The problem is that if it checks the first line and it fails the if statement, if goes through to the else statement and stops. I am trying to find a way where it will stop after the it finds the correct line but not until. If someone types in a value that isn't in the file, then it should show an error.

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  • Search field based on multiple parameter

    - by Manoj Wadhwani
    Can anybody modify this , when i insert Emp. name it go to first search and it does not check other paramete could you plz modify this sp for exact search on based on parameter. --select * from Training_TRNS --USP_SearchEmployee '','2008-04-18 00:00:00.000','','','','','' alter Procedure USP_SearchEmployee @EmpName varchar(100)=null, @DateFrom varchar(100)=null, @DateTo varchar(100)=null, @CourseName varchar(100)=null, @JobFunction varchar(100)=null, @Region varchar(100)=null, @Status varchar(100)=null AS BEGIN if (@EmpName!='' and @EmpName is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where EmpName like '%'+@EmpName+'%' END ELSE IF (@CourseName!='' and @CourseName is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where SpeCourse_ID like '%'+@CourseName+'%' END ELSE IF (@JobFunction!='' and @JobFunction is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where EmpJobFunction like '%'+@JobFunction+'%' END ELSE IF (@Region!='' and @Region is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where EmpRegion like '%'+@Region+'%' END ELSE IF (@Status!='' and @Status is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where Status like '%'+@Status+'%' END ELSE IF (@DateFrom!='' and @DateFrom is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where convert(varchar,DueDate,101) like '%'+convert(varchar,@DateFrom,101)+'%' END Else BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS END END

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  • How to Implement search through Stored Procedure

    - by Manoj Wadhwani
    Can Any budy update thie sp for search , i think i have put search condition which is not rigth . If you have expertise in sql then update it , It's very urgent i have to upload it toady .. alter Procedure USP_SearchEmployee @EmpName varchar(100)=null, @DateFrom varchar(100)=null, @DateTo varchar(100)=null, @CourseName varchar(100)=null, @JobFunction varchar(100)=null, @Region varchar(100)=null, @Status varchar(100)=null AS BEGIN if (@EmpName!='' or @EmpName is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where EmpName like '%'+@EmpName+'%' END ELSE IF (@CourseName!='' or @CourseName is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where SpeCourse_ID like '%'+@CourseName+'%' END ELSE IF (@JobFunction!='' or @JobFunction is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where EmpJobFunction like '%'+@JobFunction+'%' END ELSE IF (@Region!='' or @Region is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where EmpRegion like '%'+@Region+'%' END ELSE IF (@Status!='' or @Status is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where Status like '%'+@Status+'%' END ELSE IF (@DateFrom!='' or @DateFrom is not null) BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS where convert(varchar,DueDate,101) =convert(varchar,@DateFrom,101) END Else BEGIN select EmpName,convert(varchar,DueDate,101) as DueDate,SpeCourse_ID as CourseName, EmpJobFunction as JOBFunction,EmpRegion as Region,Status from Training_TRNS END END

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  • Convert NSData to primitive variable with ieee-754 or twos-complement ?

    - by William GILLARD
    Hi every one. I am new programmer in Obj-C and cocoa. Im a trying to write a framework which will be used to read a binary files (Flexible Image Transport System or FITS binary files, usually used by astronomers). The binary data, that I am interested to extract, can have various formats and I get its properties by reading the header of the FITS file. Up to now, I manage to create a class to store the content of the FITS file and to isolate the header into a NSString object and the binary data into a NSData object. I also manage to write method which allow me to extract the key values from the header that are very valuable to interpret the binary data. I am now trying to convert the NSData object into a primitive array (array of double, int, short ...). But, here, I get stuck and would appreciate any help. According to the documentation I have about the FITS file, I have 5 possibilities to interpret the binary data depending on the value of the BITPIX key: BITPIX value | Data represented 8 | Char or unsigned binary int 16 | 16-bit two's complement binary integer 32 | 32-bit two's complement binary integer 64 | 64-bit two's complement binary integer -32 | IEEE single precision floating-point -64 | IEEE double precision floating-point I already write the peace of code, shown bellow, to try to convert the NSData into a primitive array. // self reefer to my FITS class which contain a NSString object // with the content of the header and a NSData object with the binary data. -(void*) GetArray { switch (BITPIX) { case 8: return [self GetArrayOfUInt]; break; case 16: return [self GetArrayOfInt]; break; case 32: return [self GetArrayOfLongInt]; break; case 64: return [self GetArrayOfLongLong]; break; case -32: return [self GetArrayOfFloat]; break; case -64: return [self GetArrayOfDouble]; break; default: return NULL; } } // then I show you the method to convert the NSData into a primitive array. // I restrict my example to the case of 'double'. Code is similar for other methods // just change double by 'unsigned int' (BITPIX 8), 'short' (BITPIX 16) // 'int' (BITPIX 32) 'long lon' (BITPIX 64), 'float' (BITPIX -32). -(double*) GetArrayOfDouble { int Nelements=[self NPIXEL]; // Metod to extract, from the header // the number of element into the array NSLog(@"TOTAL NUMBER OF ELEMENTS [%i]\n",Nelements); //CREATE THE ARRAY double (*array)[Nelements]; // Get the total number of bits in the binary data int Nbit = abs(BITPIX)*GCOUNT*(PCOUNT + Nelements); // GCOUNT and PCOUNT are defined // into the header NSLog(@"TOTAL NUMBER OF BIT [%i]\n",Nbit); int i=0; //FILL THE ARRAY double Value; for(int bit=0; bit < Nbit; bit+=sizeof(double)) { [Img getBytes:&Value range:NSMakeRange(bit,sizeof(double))]; NSLog(@"[%i]:(%u)%.8G\n",i,bit,Value); (*array)[i]=Value; i++; } return (*array); } However, the value I print in the loop are very different from the expected values (compared using official FITS software). Therefore, I think that the Obj-C double does not use the IEEE-754 convention as well as the Obj-C int are not twos-complement. I am really not familiar with this two convention (IEEE and twos-complement) and would like to know how I can do this conversion with Obj-C. In advance many thanks for any help or information.

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  • How do I convert Data::Dumper output back into a Perl data structure?

    - by newbee_me
    Hi all! I was wondering if you could shed some lights regarding the code I've been doing for a couple of days. I've been trying to convert a Perl-parsed hash back to XML using the XMLout() and XMLin() method and it has been quite successful with this format. #!/usr/bin/perl -w use strict; # use module use IO::File; use XML::Simple; use XML::Dumper; use Data::Dumper; my $dump = new XML::Dumper; my ( $data, $VAR1 ); Topology:$VAR1 = { 'device' => { 'FOC1047Z2SZ' => { 'ChassisID' => '2009-09', 'Error' => undef, 'Group' => { 'ID' => 'A1', 'Type' => 'Base' }, 'Model' => 'CATALYST', 'Name' => 'CISCO-SW1', 'Neighbor' => {}, 'ProbedIP' => 'TEST', 'isDerived' => 0 } }, 'issues' => [ 'TEST' ] }; # create object my $xml = new XML::Simple (NoAttr=>1, RootName=>'data', SuppressEmpty => 'true'); # convert Perl array ref into XML document $data = $xml->XMLout($VAR1); #reads an XML file my $X_out = $xml->XMLin($data); # access XML data print Dumper($data); print "STATUS: $X_out->{issues}\n"; print "CHASSIS ID: $X_out->{device}{ChassisID}\n"; print "GROUP ID: $X_out->{device}{Group}{ID}\n"; print "DEVICE NAME: $X_out->{device}{Name}\n"; print "DEVICE NAME: $X_out->{device}{name}\n"; print "ERROR: $X_out->{device}{error}\n"; I can access all the element in the XML with no problem. But when I try to create a file that will house the parsed hash, problem arises because I can't seem to access all the XML elements. I guess, I wasn't able to unparse the file with the following code. #!/usr/bin/perl -w use strict; #!/usr/bin/perl # use module use IO::File; use XML::Simple; use XML::Dumper; use Data::Dumper; my $dump = new XML::Dumper; my ( $data, $VAR1, $line_Holder ); #this is the file that contains the parsed hash my $saveOut = "C:/parsed_hash.txt"; my $result_Holder = IO::File->new($saveOut, 'r'); while ($line_Holder = $result_Holder->getline){ print $line_Holder; } # create object my $xml = new XML::Simple (NoAttr=>1, RootName=>'data', SuppressEmpty => 'true'); # convert Perl array ref into XML document $data = $xml->XMLout($line_Holder); #reads an XML file my $X_out = $xml->XMLin($data); # access XML data print Dumper($data); print "STATUS: $X_out->{issues}\n"; print "CHASSIS ID: $X_out->{device}{ChassisID}\n"; print "GROUP ID: $X_out->{device}{Group}{ID}\n"; print "DEVICE NAME: $X_out->{device}{Name}\n"; print "DEVICE NAME: $X_out->{device}{name}\n"; print "ERROR: $X_out->{device}{error}\n"; Do you have any idea how I could access the $VAR1 inside the text file? Regards, newbee_me

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  • Using Taylor Polynomials Programmatically in Maple

    - by kzh
    I am trying to use a Taylor polynomial programmatically in Maple, but the following does not seem to work... T[6]:=taylor(sin(x),x=Pi/4,6);convert(T[6], polynom, x); f:=proc(x) convert(T[6], polynom, x); end proc; f(1); All of the following also do not work: f:=convert(T[6], polynom); f:=convert(T[6], polynom, x); f:=x->convert(T[6], polynom); f:=x->convert(T[6], polynom, x);. Is there a way of doing this without copying and pasting the output of convert into the definition of f?

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  • Convert raw IMAP server data into local folders, then upload partial dataset to new IMAP server?

    - by Manca Weeks
    I am transitioning a company with about 30 IMAP accounts, loaded with data (about 77GB total), to a new email host. The majority of the data will be converted into a local archive and distributed to the company computers as a static reference data set. The server side folders the users absolutely cannot do without being on the server will be uploaded back to the new server. I used Mac OS X Mail (Snow Leopard 10.6.6) to download the content. I notice some messages have the name [xxx].partial.emlx, which leads me to believe they have not been downloaded all the way. I have root access to the mail server data and could download the IMAP server data via FTP. I am not sure what utility to use to convert that data to local Mail.app mailboxes. Furthermore, I would appreciate any input on the best way to upload a portion of the data to the new server (GoDaddy), preserving the original dates of the messages. edit OK - forget the raw server data. I found a script that apparently does pretty good archiving IMAP folders to local mbx files. My main quest now is to batch upload a mailbox hierarchy to the new IMAP server without having to start-stop and deal with similar issues. Anyone know of a utility (hopefully for OS X, but if not, I'll fire up my XP virtual system...) that would be capable of this? Thanks, M

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  • Best way to convert episodic DVDs for Windows Media Center?

    - by Roger Lipscombe
    I'm archiving my DVD collection. My goal is to be able to play them back in Windows Media Center. For feature-length DVDs, I'm using AnyDVD and CloneDVD, which is working well. For playing back TV shows (and other episodic content), I'm using Media Browser, which doesn't support a VIDEO_TS folder per episode. It expects the shows to be broken up into one file per episode (e.g. "Willo the Wisp - S01E12.avi"). For this, I'm attempting to use Handbrake, which, for extracting the episodes from DVD (or already-ripped VIDEO_TS folder), is working pretty well. The problem that I have is that the default x264 encoder over-compresses the resulting video stream, which results in hideous artifacts in animated shows. The aforementioned Willo the Wisp is a particularly bad example, because the original DVD is particularly "noisy". If I switch to using the ffmpeg encoder, the artifacts are gone in Windows Media Player, but I can't get the resulting files to play back in Windows Media Center. I see the first frame, and then there's an error message. I've installed the CCCP codec collection, but it doesn't seem to have made any difference. So: what's the best way to convert VIDEO_TS to individual episode files for playback in Windows Media Center?

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  • How to convert a raw disk image to a copy-on-write image based on another image for use with kvm and

    - by Jean-Paul Calderone
    I have a virtual Windows machine running on kvm. Presently it has a 90GB raw disk image. I would like to clone this VM without having to keep two copies of the 90GB raw disk image around. It seems like a good approach for doing this is to make two new qcow or qcow2 images based on the original. First I converted the raw image to a qcow2 image: qemu-img convert -O qcow2 basewindowsxp.img basewindowsxp.qcow2 Then I tried creating a new image backed by this: qemu-img create -F qcow2 -f qcow2 -b `pwd`/basewindowsxp.qcow2 windowsxp-1.qcow2 Then I used virt-manager to point the original VM at windowsxp-1.qcow2. However, when I try to start up the VM in this new configuration, virt-manager reports an error: Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/engine.py", line 588, in run_domain vm.startup() File "/usr/share/virt-manager/virtManager/domain.py", line 150, in startup self._backend.create() File "/usr/lib/python2.6/dist-packages/libvirt.py", line 300, in create if ret == -1: raise libvirtError ('virDomainCreate() failed', dom=self) libvirtError: internal error unable to start guest: qemu: could not open disk image /var/lib/libvirt/images/windowsxp-1.qcow2 The error suggests that the filename was misspecified or that the filesystem permissions are too restrictive, but neither of these is the case: $ ls -l /var/lib/libvirt/images/windowsxp-1.qcow2 -rwxrwxrwx 1 root root 262144 2010-05-27 08:32 /var/lib/libvirt/images/windowsxp-1.qcow2 Why won't virt-manager start this vm?

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  • Can I convert an existing Firefox installation to ESR without a re-install?

    - by Iszi
    It took some jumping through hoops (including a mailing list subscription that I apparently didn't need) but I finally found where to download the Firefox ESR. This is great for fresh installs, but I was wondering if there's a way to simply convert existing installations to the ESR configuration without having to do a full install. As I understand it, the only difference between ESR and regular Firefox will be how they receive updates. After the new standard version of Firefox comes out, ESR releases will only receive critical security updates and bug fixes for the remainder of their support life. Newer versions of Firefox's standard build will have all the latest and greatest features, while ESR releases are meant to provide stability for environments that can't be expected to keep up with a new full version number change as often as Mozilla does them. In regular Firefox, the About screen shows that I am using the "release" update channel. Is switching to ESR really just a matter of switching the update channel? I presume this can be done in about:config by changing app.update.channel and probably also app.update.url. However, I don't know what these values should be for ESR or if anything else should be tweaked. So, is it possible to switch to ESR without a reinstall and, if so, how? (Note: While this question was written originally for Firefox 10, I expect any answers will apply to future ESR versions as well.)

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  • Is this casting safe?

    - by Itsik
    I need to write a Util function (in my c++cli app) that converts a String to a Double or Float or Int. template<typename T> static T MyConvert(String^ str) { return static_cast<T>(System::Convert::ToDouble(str)); } Is this safe? Can it somehow convert 2 to 1.999 and then to 1 if I call MyConvert<int>("2") ? I was wondering why the Convert class isn't templated in the first place? (That would let me call Convert<T> instead of Convert.ToDouble() for all types) This is C++/Cli so I can use any convert methods in c++ or .net, but I only know Convert.ToDouble()|ToString()|ToInt32()) Thanks

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  • I have a password protected USB drive with hidden partition, how to convert to normal USB drive?

    - by deddebme
    I have a generic USB drive which has password protection, and I want to stop this password protection mechanism and to use it as a normal 8GB USB drive. I received this USB drive as a gift in Hong Kong, and there was no instruction menu whatsoever, not even the manufacturer name. When I plug the drive in Windows XP, the removable drive comes up as a read only 5.28MB partition with two files. When I try to add or remove any files or formatting it, it will says the drive is write protected. After launching the Login.exe and typed in the password, a 8GB read/writeable partition will be shown, and I'm free to do anything to it. But once after the drive is unplugged and replugged, the same read only partition will still comes out no matter what I did to the hidden partition. Anyone knows about this kind if USB drive? What did the manufacturer do to hide the partition? Is there a way to "low-level" formatting this drive to convert (or revert) it to a normal drive? Before typing in the password: After typing in the password:

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  • How can I get ffmpeg to convert a .mov to a .gif?

    - by user29336
    I'm trying to convert a .mov to a .gif and I'm not having success. Here's the error: ffmpeg -pix_fmt rgb24 -i yesbuddy.mov output.gif ffmpeg version 0.11.1 Copyright (c) 2000-2012 the FFmpeg developers built on Jun 12 2012 17:47:34 with clang 2.1 (tags/Apple/clang-163.7.1) configuration: --prefix=/usr/local/Cellar/ffmpeg/0.11.1 --enable-shared --enable-gpl --enable-version3 --enable-nonfree --enable-hardcoded-tables --enable-libfreetype --cc=/usr/bin/clang --enable-libx264 --enable-libfaac --enable-libmp3lame --enable-librtmp --enable-libtheora --enable-libvorbis --enable-libvpx --enable-libxvid --enable-libopencore-amrnb --enable-libopencore-amrwb --enable-libass --enable-libvo-aacenc --disable-ffplay libavutil 51. 54.100 / 51. 54.100 libavcodec 54. 23.100 / 54. 23.100 libavformat 54. 6.100 / 54. 6.100 libavdevice 54. 0.100 / 54. 0.100 libavfilter 2. 77.100 / 2. 77.100 libswscale 2. 1.100 / 2. 1.100 libswresample 0. 15.100 / 0. 15.100 libpostproc 52. 0.100 / 52. 0.100 Option pixel_format not found. If I leave out the -pix_fmt rgb24 part it complains. Thoughts on how to fix?

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  • C#/.NET Little Pitfalls: The Dangers of Casting Boxed Values

    - by James Michael Hare
    Starting a new series to parallel the Little Wonders series.  In this series, I will examine some of the small pitfalls that can occasionally trip up developers. Introduction: Of Casts and Conversions What happens when we try to assign from an int and a double and vice-versa? 1: double pi = 3.14; 2: int theAnswer = 42; 3:  4: // implicit widening conversion, compiles! 5: double doubleAnswer = theAnswer; 6:  7: // implicit narrowing conversion, compiler error! 8: int intPi = pi; As you can see from the comments above, a conversion from a value type where there is no potential data loss is can be done with an implicit conversion.  However, when converting from one value type to another may result in a loss of data, you must make the conversion explicit so the compiler knows you accept this risk.  That is why the conversion from double to int will not compile with an implicit conversion, we can make the conversion explicit by adding a cast: 1: // explicit narrowing conversion using a cast, compiler 2: // succeeds, but results may have data loss: 3: int intPi = (int)pi; So for value types, the conversions (implicit and explicit) both convert the original value to a new value of the given type.  With widening and narrowing references, however, this is not the case.  Converting reference types is a bit different from converting value types.  First of all when you perform a widening or narrowing you don’t really convert the instance of the object, you just convert the reference itself to the wider or narrower reference type, but both the original and new reference type both refer back to the same object. Secondly, widening and narrowing for reference types refers the going down and up the class hierarchy instead of referring to precision as in value types.  That is, a narrowing conversion for a reference type means you are going down the class hierarchy (for example from Shape to Square) whereas a widening conversion means you are going up the class hierarchy (from Square to Shape).  1: var square = new Square(); 2:  3: // implicitly convers because all squares are shapes 4: // (that is, all subclasses can be referenced by a superclass reference) 5: Shape myShape = square; 6:  7: // implicit conversion not possible, not all shapes are squares! 8: // (that is, not all superclasses can be referenced by a subclass reference) 9: Square mySquare = (Square) myShape; So we had to cast the Shape back to Square because at that point the compiler has no way of knowing until runtime whether the Shape in question is truly a Square.  But, because the compiler knows that it’s possible for a Shape to be a Square, it will compile.  However, if the object referenced by myShape is not truly a Square at runtime, you will get an invalid cast exception. Of course, there are other forms of conversions as well such as user-specified conversions and helper class conversions which are beyond the scope of this post.  The main thing we want to focus on is this seemingly innocuous casting method of widening and narrowing conversions that we come to depend on every day and, in some cases, can bite us if we don’t fully understand what is going on!  The Pitfall: Conversions on Boxed Value Types Can Fail What if you saw the following code and – knowing nothing else – you were asked if it was legal or not, what would you think: 1: // assuming x is defined above this and this 2: // assignment is syntactically legal. 3: x = 3.14; 4:  5: // convert 3.14 to int. 6: int truncated = (int)x; You may think that since x is obviously a double (can’t be a float) because 3.14 is a double literal, but this is inaccurate.  Our x could also be dynamic and this would work as well, or there could be user-defined conversions in play.  But there is another, even simpler option that can often bite us: what if x is object? 1: object x; 2:  3: x = 3.14; 4:  5: int truncated = (int) x; On the surface, this seems fine.  We have a double and we place it into an object which can be done implicitly through boxing (no cast) because all types inherit from object.  Then we cast it to int.  This theoretically should be possible because we know we can explicitly convert a double to an int through a conversion process which involves truncation. But here’s the pitfall: when casting an object to another type, we are casting a reference type, not a value type!  This means that it will attempt to see at runtime if the value boxed and referred to by x is of type int or derived from type int.  Since it obviously isn’t (it’s a double after all) we get an invalid cast exception! Now, you may say this looks awfully contrived, but in truth we can run into this a lot if we’re not careful.  Consider using an IDataReader to read from a database, and then attempting to select a result row of a particular column type: 1: using (var connection = new SqlConnection("some connection string")) 2: using (var command = new SqlCommand("select * from employee", connection)) 3: using (var reader = command.ExecuteReader()) 4: { 5: while (reader.Read()) 6: { 7: // if the salary is not an int32 in the SQL database, this is an error! 8: // doesn't matter if short, long, double, float, reader [] returns object! 9: total += (int) reader["annual_salary"]; 10: } 11: } Notice that since the reader indexer returns object, if we attempt to convert using a cast to a type, we have to make darn sure we use the true, actual type or this will fail!  If the SQL database column is a double, float, short, etc this will fail at runtime with an invalid cast exception because it attempts to convert the object reference! So, how do you get around this?  There are two ways, you could first cast the object to its actual type (double), and then do a narrowing cast to on the value to int.  Or you could use a helper class like Convert which analyzes the actual run-time type and will perform a conversion as long as the type implements IConvertible. 1: object x; 2:  3: x = 3.14; 4:  5: // if you want to cast, must cast out of object to double, then 6: // cast convert. 7: int truncated = (int)(double) x; 8:  9: // or you can call a helper class like Convert which examines runtime 10: // type of the value being converted 11: int anotherTruncated = Convert.ToInt32(x); Summary You should always be careful when performing a conversion cast from values boxed in object that you are actually casting to the true type (or a sub-type). Since casting from object is a widening of the reference, be careful that you either know the exact, explicit type you expect to be held in the object, or instead avoid the cast and use a helper class to perform a safe conversion to the type you desire. Technorati Tags: C#,.NET,Pitfalls,Little Pitfalls,BlackRabbitCoder

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  • How I do VCS

    - by Wes McClure
    After years of dabbling with different version control systems and techniques, I wanted to share some of what I like and dislike in a few blog posts.  To start this out, I want to talk about how I use VCS in a team environment.  These come in a series of tips or best practices that I try to follow.  Note: This list is subject to change in the future. Always use some form of version control for all aspects of software development. Development is an evolution.  Looking back at where we were is an invaluable asset in that process.  This includes data schemas and documentation. Reverting / reapplying changes is absolutely critical for efficient development. The tools I use: Code: Hg (preferred), SVN Database: TSqlMigrations Documents: Sometimes in code repository, also SharePoint with versioning Always tag a commit (changeset) with comments This is a quick way to describe to someone else (or your future self) what the changeset entails. Be brief but courteous. One or two sentences about the task, not the actual changes. Use precommit hooks or setup the central repository to reject changes without comments. Link changesets to documentation If your project management system integrates with version control, or has a way to externally reference stories, tasks etc then leave a reference in the commit.  This helps locate more information about the commit and/or related changesets. It’s best to have a precommit hook or system that requires this information, otherwise it’s easy to forget. Ability to work offline is required, including commits and history Yes this requires a DVCS locally but doesn’t require the central repository to be a DVCS.  I prefer to use either Git or Hg but if it isn’t possible to migrate the central repository, it’s still possible for a developer to push / pull changes to that repository from a local Hg or Git repository. Never lock resources (files) in a central repository… Rude! We have merge tools for a reason, merging sucked a long time ago, it doesn’t anymore… stop locking files! This is unproductive, rude and annoying to other team members. Always review everything in your commit. Never ever commit a set of files without reviewing the changes in each. Never add a file without asking yourself, deep down inside, does this belong? If you leave to make changes during a review, start the review over when you come back.  Never assume you didn’t touch a file, double check. This is another reason why you want to avoid large, infrequent commits. Requirements for tools Quickly show pending changes for the entire repository. Default action for a resource with pending changes is a diff. Pluggable diff & merge tool Produce a unified diff or a diff of all changes.  This is helpful to bulk review changes instead of opening each file. The central repository is not your own personal dump yard.  Breaking this rule is a sure fire way to get the F bomb dropped in front of your name, multiple times. If you turn on Visual Studio’s commit on closing studio option, I will personally break your fingers. By the way, the person(s) in charge of this feature should be fired and never be allowed near programming, ever again. Commit (integrate) to the central repository / branch frequently I try to do this before leaving each day, especially without a DVCS.  One never knows when they might need to work from remote the following day. Never commit commented out code If it isn’t needed anymore, delete it! If you aren’t sure if it might be useful in the future, delete it! This is why we have history. If you don’t know why it’s commented out, figure it out and then either uncomment it or delete it. Don’t commit build artifacts, user preferences and temporary files. Build artifacts do not belong in VCS, everything in them is present in the code. (ie: bin\*, obj\*, *.dll, *.exe) User preferences are your settings, stop overriding my preferences files! (ie: *.suo and *.user files) Most tools allow you to ignore certain files and Hg/Git allow you to version this as an ignore file.  Set this up as a first step when creating a new repository! Be polite when merging unresolved conflicts. Count to 10, cuss, grab a stress ball and realize it’s not a big deal.  Actually, it’s an opportunity to let you know that someone else is working in the same area and you might want to communicate with them. Following the other rules, especially committing frequently, will reduce the likelihood of this. Suck it up, we all have to deal with this unintended consequence at times.  Just be careful and GET FAMILIAR with your merge tool.  It’s really not as scary as you think.  I personally prefer KDiff3 as its merging capabilities rock. Don’t blindly merge and then blindly commit your changes, this is rude and unprofessional.  Make sure you understand why the conflict occurred and which parts of the code you want to keep.  Apply scrutiny when you commit a manual merge: review the diff! Make sure you test the changes (build and run automated tests) Become intimate with your version control system and the tools you use with it. Avoid trial and error as much as is possible, sit down and test the tool out, read some tutorials etc.  Create test repositories and walk through common scenarios. Find the most efficient way to do your work.  These tools will be used repetitively, so inefficiencies will add up. Sometimes this involves a mix of tools, both GUI and CLI. I like a combination of both Tortoise Hg and hg cli to get the job efficiently. Always tag releases Create a way to find a given release, whether this be in comments or an explicit tag / branch.  This should be readily discoverable. Create release branches to patch bugs and then merge the changes back to other development branch(es). If using feature branches, strive for periodic integrations. Feature branches often cause forked code that becomes irreconcilable.  Strive to re-integrate somewhat frequently with the branch this code will ultimately be merged into.  This will avoid merge conflicts in the future. Feature branches are best when they are mutually exclusive of active development in other branches. Use and abuse local commits , at least one per task in a story. This builds a trail of changes in your local repository that can be pushed to a central repository when the story is complete. Never commit a broken build or failing tests to the central repository. It’s ok for a local commit to break the build and/or tests.  In fact, I encourage this if it helps group the changes more logically.  This is one of the main reasons I got excited about DVCS, when I wanted more than one changeset for a set of pending changes but some files could be grouped into both changesets (like solution file / project file changes). If you have more than a dozen outstanding changed resources, there should probably be more than one commit involved. Exceptions when maintaining code bases that require shotgun surgery, in this case, it’s a design smell :) Don’t version sensitive information Especially usernames / passwords   There is one area I haven’t found a solution I like yet: versioning 3rd party libraries and/or code.  I really dislike keeping any assemblies in the repository, but seems to be a common practice for external libraries.  Please feel free to share your ideas about this below.    -Wes

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  • How can I get rid of just the untracked files in git?

    - by dukeofgaming
    In Mercurial I can do this with the bundled Purge Extension and executing the following command: hg purge Also good to get rid of ignored files: hg purge --all I'm curious about the most practical/used equivalent solution in git. Edit: I want to just get rid of the untracked files, not reset everything (e.g. suppose I have a program generating cache files or generated code and I want to delete them with git's help)

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  • The ping response time doesn't reflect the real network response time

    - by yangchenyun
    I encountered a weird problem that the response time returned by ping is almost fixed at 98ms. Either I ping the gateway, or I ping a local host or a internet host. The response time is always around 98ms although the actual delay is obvious. However, the reverse ping (from a local machine to this host) works properly. The following is my route table and the result: route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.1.1 0.0.0.0 UG 100 0 0 eth1 60.194.136.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 eth1 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 # ping the gateway ping 192.168.1.1 PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data. 64 bytes from 192.168.1.1: icmp_req=1 ttl=64 time=98.7 ms 64 bytes from 192.168.1.1: icmp_req=2 ttl=64 time=97.0 ms 64 bytes from 192.168.1.1: icmp_req=3 ttl=64 time=96.0 ms 64 bytes from 192.168.1.1: icmp_req=4 ttl=64 time=94.9 ms 64 bytes from 192.168.1.1: icmp_req=5 ttl=64 time=94.0 ms ^C --- 192.168.1.1 ping statistics --- 5 packets transmitted, 5 received, 0% packet loss, time 4004ms rtt min/avg/max/mdev = 94.030/96.149/98.744/1.673 ms #ping a local machine ping 192.168.1.88 PING 192.168.1.88 (192.168.1.88) 56(84) bytes of data. 64 bytes from 192.168.1.88: icmp_req=1 ttl=64 time=98.7 ms 64 bytes from 192.168.1.88: icmp_req=2 ttl=64 time=96.9 ms 64 bytes from 192.168.1.88: icmp_req=3 ttl=64 time=96.0 ms 64 bytes from 192.168.1.88: icmp_req=4 ttl=64 time=95.0 ms ^C --- 192.168.1.88 ping statistics --- 4 packets transmitted, 4 received, 0% packet loss, time 3003ms rtt min/avg/max/mdev = 95.003/96.696/98.786/1.428 ms #ping a internet host ping google.com PING google.com (74.125.128.139) 56(84) bytes of data. 64 bytes from hg-in-f139.1e100.net (74.125.128.139): icmp_req=1 ttl=42 time=99.8 ms 64 bytes from hg-in-f139.1e100.net (74.125.128.139): icmp_req=2 ttl=42 time=99.9 ms 64 bytes from hg-in-f139.1e100.net (74.125.128.139): icmp_req=3 ttl=42 time=99.9 ms 64 bytes from hg-in-f139.1e100.net (74.125.128.139): icmp_req=4 ttl=42 time=99.9 ms ^C64 bytes from hg-in-f139.1e100.net (74.125.128.139): icmp_req=5 ttl=42 time=99.9 ms --- google.com ping statistics --- 5 packets transmitted, 5 received, 0% packet loss, time 32799ms rtt min/avg/max/mdev = 99.862/99.925/99.944/0.284 ms I am running iperf to test the bandwidth, the rate is quite low for a LAN connection. iperf -c 192.168.1.87 -t 50 -i 10 -f M ------------------------------------------------------------ Client connecting to 192.168.1.87, TCP port 5001 TCP window size: 0.06 MByte (default) ------------------------------------------------------------ [ 4] local 192.168.1.139 port 54697 connected with 192.168.1.87 port 5001 [ ID] Interval Transfer Bandwidth [ 4] 0.0-10.0 sec 6.12 MBytes 0.61 MBytes/sec [ 4] 10.0-20.0 sec 6.38 MBytes 0.64 MBytes/sec [ 4] 20.0-30.0 sec 6.38 MBytes 0.64 MBytes/sec [ 4] 30.0-40.0 sec 6.25 MBytes 0.62 MBytes/sec [ 4] 40.0-50.0 sec 6.38 MBytes 0.64 MBytes/sec [ 4] 0.0-50.1 sec 31.6 MBytes 0.63 MBytes/sec

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  • Java+DOM: How do I convert a DOM tree without namespaces to a namespace-aware DOM tree?

    - by java.is.for.desktop
    Hello, everyone! I receive a Document (DOM tree) from a certain API (not in JDK). Sadly, this Document is not namespace-aware. As far as I know DOM, once generated, namespace-awareness can't be "added" afterwards. When converting this Document using a Transformer to a string, the XML is correct. Elements have xmlns:... attributes and name prefixes. But from the DOM point of view, there are no namespaces and no prefixes. I need to be able to convert this Document into a new Document which is namespace-aware. Yes, I could do this by just converting it to a string and back to DOM with namespaces enabled. But: nodes of the original tree have user-objects set. Converting to string and back would make a mapping of these user-objects to the new Document very complicated, if not impossible. So I really need a way to convert non-namespace DOM to namespace DOM. Are there any more-or-less straightforward solutions for this? Worst case (what I'm hoping to avoid) would be to manually iterate through old Document tree and create new namespace-aware Node for each old Node. Doing so, one had to manually "parse" namespace prefixes, watch out for xmlns-attributes, and maintain a mapping between prefixes and namespace-URIs. Lots of things to go wrong.

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  • Is there a better way to create a generic convert string to enum method or enum extension?

    - by Kelsey
    I have the following methods in an enum helper class (I have simplified it for the purpose of the question): static class EnumHelper { public enum EnumType1 : int { Unknown = 0, Yes = 1, No = 2 } public enum EnumType2 : int { Unknown = 0, Dog = 1, Cat = 2, Bird = 3 } public enum EnumType3 : int { Unknown = 0, iPhone = 1, Andriod = 2, WindowsPhone7 = 3, Palm = 4 } public static EnumType1 ConvertToEnumType1(string value) { return (string.IsNullOrEmpty(value)) ? EnumType1.Unknown : (EnumType1)(Enum.Parse(typeof(EnumType1), value, true)); } public static EnumType2 ConvertToEnumType2(string value) { return (string.IsNullOrEmpty(value)) ? EnumType2.Unknown : (EnumType2)(Enum.Parse(typeof(EnumType2), value, true)); } public static EnumType3 ConvertToEnumType3(string value) { return (string.IsNullOrEmpty(value)) ? EnumType3.Unknown : (EnumType3)(Enum.Parse(typeof(EnumType3), value, true)); } } So the question here is, can I trim this down to an Enum extension method or maybe some type of single method that can handle any type. I have found some examples to do so with basic enums but the difference in my example is all the enums have the Unknown item that I need returned if the string is null or empty (if no match is found I want it to fail). Looking for something like the following maybe: EnumType1 value = EnumType1.Convert("Yes"); // or EnumType1 value = EnumHelper.Convert(EnumType1, "Yes"); One function to do it all... how to handle the Unknown element is the part that I am hung up on.

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  • How to convert CMYK to RGB programmatically in indesign.

    - by BBDeveloper
    Hi, I have a CMYK colorspace in indesign, i want to convert that as RGB color space, I got some codes, but I am getting incorrect data. Some of the codes which I tried are given below double cyan = 35.0; double magenta = 29.0; double yellow = 0.0; double black = 16.0; cyan = Math.min(255, cyan + black); //black is from K magenta = Math.min(255, magenta + black); yellow = Math.min(255, yellow + black); l_res[0] = 255 - cyan; l_res[1] = 255 - magenta; l_res[2] = 255 - yellow; @Override public float[] toRGB(float[] p_colorvalue) { float[] l_res = {0,0,0}; if (p_colorvalue.length >= 4) { float l_black = (float)1.0 - p_colorvalue[3]; l_res[0] = l_black * ((float)1.0 - p_colorvalue[0]); l_res[1] = l_black * ((float)1.0 - p_colorvalue[1]); l_res[2] = l_black * ((float)1.0 - p_colorvalue[2]); } return (l_res); } The values are C=35, M = 29, Y = 0, K = 16 in CMYK color space and the correct RGB values are R = 142, G = 148, B = 186. In adobe indesign, using swatches we can change the mode to CMYK or to RGB. But I want to do that programmatically, Can I get any algorithm to convert CMYK to RGB which will give the correct RGB values. And one more question, if the alpha value for RGB is 1 then what will be the alpha value for CMYK? Can anyone help me to solve these issues... Thanks in advance.

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  • Hi, How can I convert a dynamic web page to pdf?

    - by Jemma Diampuan
    I have a dynamic webpage that I created using html and php... I already have sample codes that can convert a static web page to pdf... But my problem is my web page is dynamic... So is there a way to convert my page to pdf? If yes, please provide some easy to understand codes... thank... Anyway, here is my code: //session variable $userID = 1; $receipt = &new Receipt(); $receipt->queryReceiptInfo($userID); $receiptID = $receipt->getReceiptID(); $receiptIssueDate = $receipt->getReceiptIssueDate(); $customer = $receipt->getCustomer(); $salesID = $receipt->getSalesID(); $salesDetail = &new SalesDetail($salesID); $salesDetails = $salesDetail->viewSalesDetail(); //session variable $businessID = 1; $business = &new Business('', $businessID); $business->queryBusinessName(); $businessName = $business->getBusinessName(); $rows = sizeof($salesDetails); $columns = sizeof($salesDetails[0]); ? Receipt No. Date Issued Business Customer Item Quantity Sub-Total "; for($j = 0; $j ".$salesDetails[$i][$j].""; } $totalPrice += (double)$salesDetails[$i][2]; echo ""; } ? Total Price

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  • How to convert String format dates to Date format dates?

    - by Jani Bela
    I have a string with dates it looks like: "20120316 20120317 20120318" ... I store this dates in this format, but I would like to make a Date array from these numbers with the format 03/16 03/17 03/18 ... So far: String[] DailyDatasOnce2 = DatesOnce.split(" "); DailyDatasOnce = new String[DailyDatasOnce2.length]; for (int i=0;i< (DailyDatasOnce2.length) ;i++){ DailyDatasOnce[i]=DailyDatasOnce2[i]; } datumok = new Date[DailyDatasOnce.length]; for (int i=0;i< (DailyDatasOnce.length) ;i++){ SimpleDateFormat curFormater = new SimpleDateFormat("yyyyMMdd"); java.util.Date dateObj = null; java.util.Date dateObj2 = null; try { dateObj = curFormater.parse(DailyDatasOnce[i]); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } SimpleDateFormat postFormater = new SimpleDateFormat("MM/dd"); String newDateStr = postFormater.format(dateObj); try { dateObj2 = curFormater.parse(newDateStr); } catch (ParseException e) { // TODO Auto-generated catch block e.printStackTrace(); } datumok[i] = dateObj2; } So first I make a string array with the string dates (DailyDatasOnce), maybe that first for loop is useless but i can skip it. Now I make a Date array and I want to put the dates into it. I format the dates to format I want, then I try to convert them to Date format. Until the String newDateStr it is working, I manage to change the type of the date. But I get syntax error: Type mismatch: Cannot convert from java.util.date to java.sql.data. I suspect the problem but if it is not possible, how can i do this?

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